The present invention generally relates to refrigeration systems. More particularly, the invention relates to a compact refrigeration system which may be advantageously employed in a vehicle.
In some vehicles such as aircraft, refrigeration systems may be employed to perform various cooling functions. In a typical aircraft, where space is limited, it is advantageous to construct on-board refrigeration systems that occupy as little volume as possible. At the same time, it is advantageous to construct aircraft refrigeration systems with low weight and high efficiency.
It is known that incorporating suction line heat exchangers in refrigeration systems may increase temperature of refrigerant vapor at a compressor inlet. The increased temperature may reduce the amount of refrigerant that can be absorbed into lubricating oil and thereby may result in an increase of viscosity of the oil. Higher viscosity oil-refrigerant mixture may provide improved lubrication and longer life for various compressor components. Additionally, the suction line heat exchanger may minimize the amount of liquid refrigerant that enters the compressor thus adding further to higher oil viscosity.
While suction line heat exchangers are a desirable feature for refrigeration systems, their use has heretofore added substantial volume to a refrigeration system. Typically, effective suction line heat exchangers may have a volume that is about equal to the volume of a receiver of the system.
As can be seen, there is a need for an aircraft refrigeration system system in which a suction line heat exchanger may be employed and in which the suction line heat exchanger adds only minimal volume to the system.